The little four-hander "Amy and Elliot," at the Stella Adler, typifies the dozens of limited-run, limited-means L.A. showcases appearing each year as artists seek to raise their game.

The little four-hander “Amy and Elliot,” at the Stella Adler, typifies the dozens of limited-run, limited-means L.A. showcases appearing each year as artists seek to raise their game. Ryan Eggold — sensitive, studly high school teacher on Fox’s reconstituted “90210” — assumes triple duty as scribe, helmer and star. If he writes far better for himself than for his colleagues, and if his dramaturgical command is rickety at best, he comes up with an engaging portrayal of a raffish no-account afflicted with Peter Pan Syndrome.

The titular couple (Alexandra Breckenridge as the distaff member) are set up in stock “Will & Grace” fashion: best friends since childhood; daily gameplaying and japery; fear of commitment; yada yada. Amy’s about to marry a doctor (Robert Baker) but Elliot’s afraid of losing her, his open boxes of Cap’n Crunch signaling a heavy-duty case of arrested development.

The ensuing hijinks strain credibility. Nonstop discussions of relationships and life issues are always completely on point, lacking

subtext or texture. (Wouldn’t lifelong BFFs have specific things on their minds? We never even find out what Amy and Elliot do for a living.)

A flyer at sexual tension between the two is a non-starter, and the big twist in act two involving political activist Jolene (“90210″ regular Gillian Zinser) achieves surprise without being especially plausible.

Still, the pacing is brisk, the blocking clean and the relaxed performances are nicely modulated to the small space. And Eggold is wonderful, a full repertoire of aw-shucks gestures and amusing line readings showcasing — as a showcase ought to do — his readiness for bigger and better things.